Explanation

• The police system was first established by Umar ibn al-Khattab.
• He was the second Caliph (634–644 CE).
• A proper system of law enforcement and public safety was organized.
• He also introduced the Hijri calendar.
• He established systems like Bait-ul-Mal (treasury) and judiciary.

Last verified on 30-04-2026

Explanation

• Bi’r Ruma was a famous well in Madina.
• It was known for its sweet and fresh water.
• The Prophet Muhammad ﷺ encouraged its purchase for public use.
• It was bought by Uthman ibn Affan (R.A).
• It became a charitable endowment (Waqf) for Muslims.

Last verified on 28-04-2026

Explanation

• Al-Baqarah (The Cow or The Heifer) is the second and longest chapter of the Quran, with 286 verses.
• It derives its name from the story of the cow (vv. 67-73).
• Verse 282, the longest verse, is known as 'āyatu d-dayn.
• It consists of 25,500 letters and is positioned in Juzʼ 1–3.
• The chapter has 40 Rukus.
• It is classified as Medinan.

Additional information:

• Hazrat Ibrahim (علیہ السلام) is mentioned 13 times.
• The verse 183 describes the obligation of fasting (soam).
• Surah Aal-e-Imran is the second longest surah of Holy Quran.
• Surah Al-Kausar is the shortest surah of Holy Quran.

Last verified on 30-03-2026

Explanation

• Noise intensity is measured in decibels (dB).
• It indicates the loudness of sound.
• It helps assess noise pollution in cities, industries, and traffic areas.
• Noise pollution affects hearing, stress levels, and sleep.
• Reducing exposure above 85 dB is important for health protection.

Last verified on 19-03-2026

Explanation

Explanation

• Scientific Name: Mangifera indica
  • Common Name: Mango / آم
  • Family: Anacardiaceae
  • Origin: South Asia (India, Pakistan, Bangladesh)
  • Major Cultivation: India, Pakistan, Mexico, Philippines, Thailand

Last verified on 05-02-2026

Explanation

Explanation

• Ethylene is a gaseous plant hormone that stimulates fruit ripening.
• It can inhibit vegetative growth in some plants.
• It is naturally produced by fruits like apples and bananas during maturation.

Additional information:

• Abscisic acid helps in seed dormancy and stress response.
• Auxin mainly promotes cell elongation and growth.

Last verified on 30-01-2026

Explanation

O negative (O⁻) blood group is called the universal donor.

It can be transfused to any blood group (A, B, AB, or O).

O⁻ lacks A, B, and Rh antigens, preventing immune reactions in recipients.

Explanation

• Author: Chaudhry Khaliquzzaman
• English edition published: 1961
• Urdu edition published: 1967
• Nature of book: Autobiography / Memoirs
• Topic: Pakistan Movement and political struggle

Last verified on 18-01-2026